Thermal Comfort of the Floor Supply Air Conditioning System for Different Supply-return Locations during Cooling

급배기 위치에 따른 바닥급기 공조시스템의 냉방 열환경

  • 김요셉 (한국과학기술연구원 열유동제어연구센터) ;
  • 김영일 (한국과학기술연구원 열유동제어연구센터) ;
  • 유호선 (숭실대학교 기계공학과)
  • Published : 2000.05.01

Abstract

This study numerically investigates thermal comfort in a space cooled by the floor-supply air conditioning system, in which three different supply-return locations, one floor supply-ceiling return and two floor supply-floor returns, are treated. A complementary experiment is peformed to validate the present numerical analysis, and the prediction agrees favorably with the measured data. In the numerical procedure, a simplified model mimicking the inlet flow through the diffuser is developed for efficient simulations. The calculated results show that the ceiling return type is far better in thermal comfort than the floor return ones within the extent of this study, which seems to be caused by effective vertical penetration of the supply air against natural convection. It is also revealed that the arrangement of port locations in the floor supply-floor return system has insignificant effect on the cooling performance. For selecting a proper system, other characteristics including the heating performance should be accounted for simultaneously with the present estimation.

Keywords

References

  1. ASHRAE Trans. v.95 Nordic experiences of displacement ventilation system Svensson, A. G. L.
  2. J. of Equipment Technology v.75 Status of the International Under Floor Air conditioning System Lee, Chun Sik
  3. ASHRAE Trans. v.101 Underfloor air distribution systems : Benefits and when to use the system in building design McCarry, T. B.
  4. Ventilating and Air Conditioning Modern Heating Clifford, G.
  5. ASHRAE Trans. v.95 Numerical study on diffusion field as affected by arrangement of supply and exhaust openings in conventional flow type clean room Murakami, S.;Kato, S.;Suyama, Y.
  6. ASHRAE Trans. v.101 A comparison of room air motion in a full size test room using different diffusers and operating conditions Hawkins, A. N.;Hosni, M. H.;Jones, B. N.
  7. ASHRAE Trans. v.99 Characteristics of diffuser air jets and airflow in the occupied regions of mechanically ventilated rooms - a literature review Li, Z. H.;Zhang, J. S.;Zhivov, A. M.;Christianson, L. L.
  8. Final Report, Ministry of Industry and Resources Development of Diffusers for UFAC System Kim, Y.
  9. ASHRAE Trans. v.102 Experimental study of vortex diffuser Shakerin, S.;Miller, P. L.
  10. Ministry of Science and Technology A Study on the Evaluation Method for Indoor Thermal Comfort and Air Quality (Ⅰ) Lee, C. S.
  11. Danish Technical Press Thermal Comfort Analysis and Application in Environmental Engineering Fanger, P. O.
  12. Korean J. of Air-Conditioning and Refrigeration Engineering v.7 no.2 Evaluation of Korean Thermal Sensation in Office Buildings During the Summer Season Bae, G. N.;Lee, C. H.;Lee, C. S.
  13. Moderate Thermal Environments - Determination of the PMV and PPD Indices and Specification of the Condition for Thermal Comfort ISO 7730 ISO
  14. Ergonomics of the Thermal Environment - Instruments for Measuring Physical Quantities ISO 7726 ISO
  15. ASHRAE Trans. v.95 Case studies of displacement ventilation in public halls Mathisen, H. M.
  16. 5th Int. Conf. on Air Distribution in Rooms Influence of the boundary thermal conditions on the performance of a mechanical ventilation plant in a test room Di Tommaso, R. M.;Nino, E.;Brindisi, P.;Fracastoro, G. V.
  17. ASHRAE Trans. v.99 A comparative study of room airflow numerical prediction using computational fluid dynamics and full-scale experimental measurements Weathers, J. W.;Spitler, J. D.
  18. ASHRAE Trans. v.97 Numerical prediction of horizontal nonisothermal 3-D jet in room based on the κ-ε model Murakami, S.;Kato, S.;Nakagawa H.
  19. 5th Int. Conf. on Air Distribution in Rooms Environment measurement and numerical analysis of an air conditioning system employing displacement ventilation in building displacement ventilation in building K of the head office in Tokyo Fukumoto, K.;Murata, T.
  20. ASHRAE Trans. v.98 The influence of supply and exhaust openings on ventilation efficiency in an air-conditioned room with a raised floor Murakami, S.;Kato, S.;Tanaka, T.
  21. Int. J. Heat and Mass Transfer v.18 Correlation equations for laminar and turbulent free convection from a vertical plate Churchill, S. W.;Chu, H. H. S.
  22. Thermal Environmental Conditions for Human Occupancy ANSI/ASHRAE 55-1992 ASHRAE